<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>

.bg {
            background-image: url(jdzy.png);
            background-repeat: no-repeat;
            margin: auto;
            width: 240px;
            height: 330px;
        }

        .text {
            color: white;
            padding-left: 35px;
            padding-top: 25px;
            font-size: 30px;
        }

        .text1 {
            color: white;
            padding-top: 100px;
            padding-left: 30px;
        }

        .hour {
            background-color: black;
            color: white;
            width: 35px;
            height: 35px;
            margin-top: 10px;
            margin-left: 25px;
            float: left;
            
        }

        .minute {
            background-color: black;
            color: white;
            width: 35px;
            height: 35px;
            margin-top: 10px;
            margin-left: 10px;
            float: left;
        }

        .second {
            background-color: black;
            color: white;
            width: 35px;
            height: 35px;
            margin-top: 10px;
            margin-left: 10px;
            float: left;
        }

        .hm {
            margin-top: 10px;
            margin-left: 5px;
            float: left;
            font-size: 20px;
            color:white
        }

        .ms {
            margin-top: 10px;
            margin-left: 5px;
            float: left;
            font-size: 20px;
            color:white

        }


    </style>

</head>
<body>
    <div class="bg">
        <div class="text"></div>
        <div class="text1"></div>
        <div class="hour"></div>
        <span class="hm"></span>
        <div class="minute"></div>
        <span class="ms"></span>
        <div class="second"></div>

    </div>

<script>
    var hour = document.querySelector('.hour');
    var minute = document.querySelector('.minute');
    var second = document.querySelector('.second');
    var inputTime = +new Date('2021-6-8 24:00:00')
    countDown();
    setInterval(countDown,1000);
    function countDown(){
        var nowTime = +new Date();
        var times = (inputTime-nowTime)/1000;
        var h = parseInt(times / 60 / 60 % 24);
        h = h < 10 ? '0' + h : h;
        hour.innerHTML = h;
        var m = parseInt(times / 60 % 60);
        m = m < 10 ? '0' + m : m;
            minute.innerHTML = m;
            var s = parseInt(times % 60);
            s = s < 10 ? '0' + s : s;
            second.innerHTML = s;

    }





</script>

</body>
</html>